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Homework Help: Finding the remainder

  1. May 8, 2017 #1
    1. The problem statement, all variables and given/known data
    What is the remainder when (1*1!+2*2!+.....+12*12!) Is divided by 13? Please give the answer along with the steps.

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. May 9, 2017 #2


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    Homework Helper

    We cannot give the answer. We give hints, to solve the problem by yourself.
    Read about the Forum rules:
    "Show us that you've thought about the problem.
    The forum rules require that you show an attempt at solving the problem on your own."

    What does n! mean? Can you write the expression (1*1!+2*2!+.....+12*12!) entirely with factorials?
    Note that (k+1)! = (k+1)k!, determine (k+1)! - k!.
    Last edited: May 9, 2017
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